| /* |
| * Written by Doug Lea with assistance from members of JCP JSR-166 |
| * Expert Group and released to the public domain, as explained at |
| * http://creativecommons.org/publicdomain/zero/1.0/ |
| * Other contributors include Andrew Wright, Jeffrey Hayes, |
| * Pat Fisher, Mike Judd. |
| */ |
| |
| package jsr166; |
| |
| import junit.framework.*; |
| import java.util.concurrent.atomic.AtomicLongFieldUpdater; |
| |
| public class AtomicLongFieldUpdaterTest extends JSR166TestCase { |
| volatile long x = 0; |
| int z; |
| long w; |
| |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> updaterFor(String fieldName) { |
| return AtomicLongFieldUpdater.newUpdater |
| (AtomicLongFieldUpdaterTest.class, fieldName); |
| } |
| |
| /** |
| * Construction with non-existent field throws RuntimeException |
| */ |
| public void testConstructor() { |
| try { |
| updaterFor("y"); |
| shouldThrow(); |
| } catch (RuntimeException success) { |
| assertNotNull(success.getCause()); |
| } |
| } |
| |
| /** |
| * construction with field not of given type throws IllegalArgumentException |
| */ |
| public void testConstructor2() { |
| try { |
| updaterFor("z"); |
| shouldThrow(); |
| } catch (IllegalArgumentException success) {} |
| } |
| |
| /** |
| * construction with non-volatile field throws IllegalArgumentException |
| */ |
| public void testConstructor3() { |
| try { |
| updaterFor("w"); |
| shouldThrow(); |
| } catch (IllegalArgumentException success) {} |
| } |
| |
| /** |
| * get returns the last value set or assigned |
| */ |
| public void testGetSet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(1, a.get(this)); |
| a.set(this, 2); |
| assertEquals(2, a.get(this)); |
| a.set(this, -3); |
| assertEquals(-3, a.get(this)); |
| } |
| |
| /** |
| * get returns the last value lazySet by same thread |
| */ |
| public void testGetLazySet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(1, a.get(this)); |
| a.lazySet(this, 2); |
| assertEquals(2, a.get(this)); |
| a.lazySet(this, -3); |
| assertEquals(-3, a.get(this)); |
| } |
| |
| /** |
| * compareAndSet succeeds in changing value if equal to expected else fails |
| */ |
| public void testCompareAndSet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertTrue(a.compareAndSet(this, 1, 2)); |
| assertTrue(a.compareAndSet(this, 2, -4)); |
| assertEquals(-4, a.get(this)); |
| assertFalse(a.compareAndSet(this, -5, 7)); |
| assertEquals(-4, a.get(this)); |
| assertTrue(a.compareAndSet(this, -4, 7)); |
| assertEquals(7, a.get(this)); |
| } |
| |
| /** |
| * compareAndSet in one thread enables another waiting for value |
| * to succeed |
| */ |
| public void testCompareAndSetInMultipleThreads() throws Exception { |
| x = 1; |
| final AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| |
| Thread t = new Thread(new CheckedRunnable() { |
| public void realRun() { |
| while (!a.compareAndSet(AtomicLongFieldUpdaterTest.this, 2, 3)) |
| Thread.yield(); |
| }}); |
| |
| t.start(); |
| assertTrue(a.compareAndSet(this, 1, 2)); |
| t.join(LONG_DELAY_MS); |
| assertFalse(t.isAlive()); |
| assertEquals(3, a.get(this)); |
| } |
| |
| /** |
| * repeated weakCompareAndSet succeeds in changing value when equal |
| * to expected |
| */ |
| public void testWeakCompareAndSet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| while (!a.weakCompareAndSet(this, 1, 2)); |
| while (!a.weakCompareAndSet(this, 2, -4)); |
| assertEquals(-4, a.get(this)); |
| while (!a.weakCompareAndSet(this, -4, 7)); |
| assertEquals(7, a.get(this)); |
| } |
| |
| /** |
| * getAndSet returns previous value and sets to given value |
| */ |
| public void testGetAndSet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(1, a.getAndSet(this, 0)); |
| assertEquals(0, a.getAndSet(this, -10)); |
| assertEquals(-10, a.getAndSet(this, 1)); |
| } |
| |
| /** |
| * getAndAdd returns previous value and adds given value |
| */ |
| public void testGetAndAdd() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(1, a.getAndAdd(this, 2)); |
| assertEquals(3, a.get(this)); |
| assertEquals(3, a.getAndAdd(this, -4)); |
| assertEquals(-1, a.get(this)); |
| } |
| |
| /** |
| * getAndDecrement returns previous value and decrements |
| */ |
| public void testGetAndDecrement() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(1, a.getAndDecrement(this)); |
| assertEquals(0, a.getAndDecrement(this)); |
| assertEquals(-1, a.getAndDecrement(this)); |
| } |
| |
| /** |
| * getAndIncrement returns previous value and increments |
| */ |
| public void testGetAndIncrement() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(1, a.getAndIncrement(this)); |
| assertEquals(2, a.get(this)); |
| a.set(this, -2); |
| assertEquals(-2, a.getAndIncrement(this)); |
| assertEquals(-1, a.getAndIncrement(this)); |
| assertEquals(0, a.getAndIncrement(this)); |
| assertEquals(1, a.get(this)); |
| } |
| |
| /** |
| * addAndGet adds given value to current, and returns current value |
| */ |
| public void testAddAndGet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(3, a.addAndGet(this, 2)); |
| assertEquals(3, a.get(this)); |
| assertEquals(-1, a.addAndGet(this, -4)); |
| assertEquals(-1, a.get(this)); |
| } |
| |
| /** |
| * decrementAndGet decrements and returns current value |
| */ |
| public void testDecrementAndGet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(0, a.decrementAndGet(this)); |
| assertEquals(-1, a.decrementAndGet(this)); |
| assertEquals(-2, a.decrementAndGet(this)); |
| assertEquals(-2, a.get(this)); |
| } |
| |
| /** |
| * incrementAndGet increments and returns current value |
| */ |
| public void testIncrementAndGet() { |
| AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
| a = updaterFor("x"); |
| x = 1; |
| assertEquals(2, a.incrementAndGet(this)); |
| assertEquals(2, a.get(this)); |
| a.set(this, -2); |
| assertEquals(-1, a.incrementAndGet(this)); |
| assertEquals(0, a.incrementAndGet(this)); |
| assertEquals(1, a.incrementAndGet(this)); |
| assertEquals(1, a.get(this)); |
| } |
| |
| } |